Thucydides (c. 460–c. 400 BC) was an Athenian general and historian. His History of the Peloponnesian War recounts the fifth-century BC war between Sparta and Athens. In the first sentence of the book, he describes himself: “Thucydides, an Athenian, wrote the war of the Peloponnesians and the Athenians as  they warred against each other, beginning to write as soon as the war was on foot, with expectation it should prove a great one and most worthy the relation of all that had been before it.”